less helpful

I found our last live session fun and extremely profitable. I’m grateful to everyone who participated live in the DimDim room and later in the comments.

I’d like to pull in twenty more volunteers to play around with a math problem tomorrow afternoon and test out some of my recent modifications to the instructional design. If you can commit 45 minutes, please drop a comment in the box using an email address where I can reach you tomorrow. We pulled a lot of people off the waiting list last time, so consider adding a comment even if twenty people have already signed up.

You know, Dan, I got a little confused about the time as well, because it says 3:00 Pacific STANDARD Time on your graphic, but most of us Pacific folks (if not everyone?) are on Pacific DAYLIGHT Time right now. So, I made sure to be home before 2:00, just in case, then realized I was converting backwards, so that 3:00 PST would actually be at 4:00 PDT. So I figured I’ll keep an eye on my email shortly before 3:00, and if that doesn’t work, slightly before 4:00. It sounds, from your 12:34 post (my favorite time of the day, 1-2-3-4), like it’s going to be at 3:00 pm “regular” time (i.e. PDT).

As for increasing clarity next time, perhaps do what TV show ads often do: just list Pacific and Eastern times and let the Central and Mountain folks work inward from those “boundary” times. If you wrote “3 pm Pacific/6 pm Eastern”, I imagine that would remove most (if not all) of the confusion.

And as a possibly-interesting side note, it appears that the time stamps on comments here are given in PST, so my “1:11 pm” comment was actually written at 2:11 pm on all the clocks in my house (here in Oregon, on PDT).

Trying to find another way to check the soil density, I found (on the internet of course) a range of 1-2 grams per cubic cm for desert soil, and also tried (at my son’s suggestion) lunar soil, which gave me a range of 1.58-1.74 g/cm3. I arbitrarily chose 1.6 g/cm3, which I converted to 99.9 lb/ft3. Not that far from the number we used (120 lb/ft3). Rounding to 100, I still get a yearly total of 173.25 tons of dirt. Astounding!

So, if X-Ray dug about 1000 pounds *less* of dirt each day, how much dirt are these boys digging, anyway? The 5-foot shovelers dig almost 10,000 pounds, I calculate. 3% less shovel digs approximately 10% less dirt.

Other extensions:

How much shorter would a shovel have to be for a boy to dig half as much as the others?

What size of a shovel would a (very, very small) person use to dig a hole with only 100 pounds of dirt? [Like a textbook comparison of cube-to-cylinder volumes.]